Mostly false Overinterpreted Certainty of evidence: moderate provisional C-INS-06

Insulin glargine increases cancer risk in a dose-dependent way (and long-term use increases breast cancer).

Safety note: Do not stop or reduce insulin on the basis of this claim. In type 1 diabetes and other insulin-deficient states, stopping insulin leads within hours to days to diabetic ketoacidosis, which is life-threatening. Medically accepted position (ADA Standards of Care 2026): insulin treatment is essential for people with type 1 diabetes; people on intensive insulin therapy should not stop basal insulin even when not eating. Any change of diabetes medication should be made together with the treating physician.
In short: This claim is mostly false. A randomised trial and large new-user cohorts show no dose-dependent increase in cancer with glargine; a long-term breast-cancer signal in some UK analyses has not been confirmed and appears linked to prior insulin exposure rather than to glargine.
Conclusion: Glargine does not raise overall cancer risk in a dose-dependent way; a possible long-term breast-cancer signal in some UK analyses has not been confirmed by larger new-user studies.

Original statement

وفي تحليل Hemkens الألماني على 127 ألف مريض، رفع جلارجين خطر السرطان بشكل يتناسب مع الجرعة.

verbatim according to source. Translation by the project; the Arabic wording is authoritative.

Translation

Insulin glargine increases cancer risk in a dose-dependent way (and long-term use increases breast cancer).

Origin

Source status
Archive editors
Attribution
Archive editors (not Elawady)
Origin
https://eltayebat.com/rule/insulin-injections/
Attribution uncertainty
Editorial narrative and study selection written by the archive operators.
Claimed mechanism

Mitogenic (growth-promoting) properties of glargine via IGF-1 receptor.

Claimed health effect

Cancer, breast cancer

Population concerned

Insulin-treated diabetes

Geographic restriction by Elawady

none found

Scientific assessment

Mostly false – Essential parts of the statement are not supported by the evidence or are strongly exaggerated.

Certainty of evidence: moderate – Further research may still affect the assessment.

1. What was claimed?

Glargine causes cancer, dose-dependently.

2. What is demonstrably correct?

Hemkens et al. (127,031 German patients, mean follow-up 1.63 years) found, after dose adjustment, HR 1.09/1.19/1.31 for 10/30/50 IU/day of glargine vs human insulin (A-INS-04); this triggered regulatory reviews in 2009. Jonasson et al. found a higher breast-cancer RR (1.99) in women using glargine alone (A-INS-05); Suissa et al. found a possible increase after >5 years in women previously on insulin (HR 2.7, based on 10 cases) (A-INS-06). These signals are real but hypothesis-generating.

3. What is wrong or exaggerated?

In Hemkens et al. crude cancer incidence was lower with glargine (2.14 vs 2.50 per 100 person-years; unadjusted HR 0.85); the excess appeared only after modelling with a time-at-risk-based dose, was concentrated in users of >40 IU/day, and higher dose was associated with cancer for all insulin types; the authors state that causality cannot be shown (A-INS-04). Jonasson et al. found no increase for all malignancies (RR 1.07, 0.91-1.27); the breast signal (25 cases) was absent in users of glargine plus other insulins, showed no dose trend, and the authors suggest chance (A-INS-05). Suissa et al. found no overall increase (HR 1.0, 0.7-1.4) and none in the first 5 years (HR 0.9), with no dose data (A-INS-06). The randomised ORIGIN trial found no difference in cancers (HR 1.00) (A-INS-07) and, in its cancer substudy, identical incidence, cancer mortality and site-specific cancers (I-INS-05). A meta-analysis found lower odds of cancer with glargine (OR 0.81) and no breast-cancer increase (OR 0.99), with very low-quality evidence (I-INS-06).

4. What remains unclear?

Very long-term (>10 years) breast-cancer risk has limited data. A UK CPRD cohort found HR 2.23 (1.32-3.77) for breast cancer after >5 years of glargine versus NPH, mainly in women who had used other insulins before (I-INS-124), whereas a Medicare new-user cohort of 203,159 glargine initiators found no increase by duration or dose (HR 0.97, 0.88-1.06) (I-INS-125) and a CPRD analysis found no association in insulin-naive women (HR 1.06 after >=5 years) (I-INS-127). A systematic review judged the observational evidence methodologically weak, with uncertainty remaining particularly for breast cancer (I-INS-126).

5. Which studies support it?

No study clearly supports the dose-dependent cancer claim. Partly: I-INS-124 (long-term breast-cancer signal in prevalent users). Mixed: A-INS-04 (model-dependent dose signal), A-INS-05, A-INS-06, I-INS-126, I-INS-127.

6. Which studies contradict it?

A-INS-07, I-INS-05 (ORIGIN RCT), I-INS-125 (large new-user cohort: no duration or dose effect), I-INS-06.

7. What applies to Germany and Europe?

The signal came from German data (AOK) and was reviewed by European regulators in 2009 (EMA statement not fetched in this audit; verified: false). Glargine remains approved in the EU.

8. What is known about Egypt?

Egypt has one of the highest diabetes prevalences in the region; the same drug classes and insulins are used. Access barriers and cost may make advice to stop medication attractive, which increases the practical risk of this claim. No Egypt-specific evidence changes the assessment.

9. What practical conclusion is appropriate?

The glargine-cancer alarm of 2009 was not confirmed by randomised evidence. People using glargine should not stop it out of fear of cancer.

Assessment details

Rationale for certainty of evidence

The 2009 observational signal (Hemkens) was real but inconsistent (Swedish and UK data showed no overall increase); the subsequent randomised ORIGIN cancer analysis (12,537 people, 953 cancer events, 6.2 years) found identical cancer incidence (1.32 vs 1.32 per 100 person-years), and a meta-analysis of 11 studies did not support a link (very low quality). Moderate rather than high certainty because the breast-cancer question for very long use was not fully resolved.

Source quality

Archive editorial quoting a German insurance cohort.

Regional transferability

German, Swedish, UK data; directly relevant to Europe.

Regional scope of the claim
general (biological/medical)
Last reviewed
26 October 2026 provisional

Scientific evidence in detail

Overinterpreted – A real finding exists, but the claim draws more from it than the data allow (e.g. association taken as cause, animal data applied to humans, small effect presented as large).

Research question: Does insulin glargine increase cancer risk dose-dependently, and does long-term use increase breast cancer?

Research question in detail (PECO)
Population
People with diabetes using insulin
Intervention or exposure
Insulin glargine (dose, duration)
Comparison
NPH or other insulins
Geographic scope
universal biology
Outcomes
  • Any cancer
  • Breast cancer

Study results as reported by the authors. Our assessment follows below.

What speaks for the claim?

What speaks against the claim?

What does the overall evidence say?

Editorial assessment based on the studies above – not itself a study result.

Which position is better supported?

Glargine does not increase overall cancer risk dose-dependently; a long-term breast-cancer signal exists in some UK prevalent-user analyses but is not confirmed in larger new-user cohorts.

Why some studies weigh more

RCT and large new-user cohorts outweigh prevalent-user cohorts with time-related biases.

Is a causal relationship established? Not established No consistent dose-response; signal confined to prevalent users/switchers.

Remaining uncertainty

Very long-term (>10 years) breast cancer risk in younger women.

Justified conclusion

Mostly false; breast-cancer part unresolved.

Why do studies seem to disagree?

Wu 2017 and Suissa 2011 (UK CPRD, prevalent users) vs Bradley 2020 (Medicare new users) and Peeters 2016 (CPRD, insulin-naive): differences in prevalent-user bias, prior insulin exposure and age explain much of the conflict.

Does this depend on the country?
General biological effects
European (German, UK) and US data; glargine remains approved in the EU.
Eating habits
Egyptian and European diets differ, but no dietary pattern replaces insulin in insulin-deficient diabetes.
Origin of the food
Not relevant.
Contaminants
Not relevant.
National production conditions
Not relevant.
Legal rules
Insulin is an essential medicine (WHO list) in Egypt and the EU; prescription rules not relevant to the scientific question.
Actual monitoring data
Egyptian/Middle Eastern data show severe DKA is common at presentation in children (I-INS-115, I-INS-114); no data on outcomes among Tayebat followers.

A regional difference that changes the conclusion is not supported by robust data.

Statistical re-check
  • CI symmetry and illustrative absolute excess – CIs symmetric; if causal, about 1.5-4 extra breast cancers per 1000 person-years (illustrative, not reported) recalculated
Certainty of the overall evidence (GRADE, simplified)
Main outcome
Overall cancer incidence with glargine
Starting level
high (randomised trials)
Reasons for downgrading
  • imprecision for breast cancer beyond 6 years
Result
moderate

Simplified assessment by a single reviewer, following the GRADE approach; not a formal GRADE panel. GRADE rates the body of evidence for one outcome, not individual studies.

Clinical guidelines and official statements checked
  • ADA: 9. Pharmacologic Approaches to Glycemic Treatment: Standards of Care in Diabetes-2026 (I-ODD-16) (2026) · Original publication
    'Insulin treatment is essential for individuals with type 1 diabetes'; insulin to be considered in T2D when A1C >10%, glucose >=300 mg/dL or catabolic features (as recorded for I-ODD-16).
Search strategy

Documented literature searches for this review (search strings in the original database syntax).

DatabaseDateSearchLooking forHitsIncluded
PubMed26 October 2026"insulin glargine" AND (cancer OR "breast cancer") AND (cohort) AND (multinational OR "five European" OR Nordic OR "long-term")both directions7
PubMed26 October 2026("insulin glargine" OR "long-acting insulin analog*") AND "breast cancer" AND (meta-analysis[pt] OR systematic review[pt])both directions5
Europe PMC26 October 2026(TITLE:"glargine") AND (TITLE:"cancer") AND PUB_YEAR:[2013 TO 2026]both directions11

How deeply was this checked?

11 linked studies: 5 checked in full text (5 of them with a structured risk-of-bias assessment), 6 on the basis of the abstract, 0 bibliographically only. No formal assessment with two independent reviewers and no independent human expert review has taken place yet.

Last scientific review: 26 October 2026

History of the verdict
  1. 25 October 2026 · Phase 1 · Initial assessment: Mostly false (moderate)
  2. 26 October 2026 · Phase 4 (systematic evidence review) · Re-examined with extended evidence; verdict unchanged: Mostly false (moderate)
    New supporting (Wu 2017) and contradicting (Bradley 2020, Peeters 2016) cohorts balance; the overall-cancer and dose parts remain contradicted by RCT and large cohorts; breast cancer long-term remains uncertain.
    New sources: I-INS-124 I-INS-125 I-INS-126 I-INS-127

In plain language

In 2009 a German database study suggested that the long-acting insulin glargine might raise cancer risk. Other studies did not find the same thing, and a large randomised trial that followed over 12,000 people for six years found exactly the same cancer rate with and without glargine. The early alarm has therefore not been confirmed.

Studies on this claim

Studies supporting the claim (1)

  • Long-term glargine use and breast cancer in UK women

    Wu JW et al.. J Clin Oncol 2017 · PMID 28953430 · DOI 10.1200/JCO.2017.73.4491
    Cohort studyindependent cross-checkabstract checked★ key study

    After more than 5 years, glargine users had about twice the breast-cancer rate of NPH users, mainly among women who had used other insulin before.

    Long-term glargine associated with breast cancer (HR 2.23 after >5 years); not replicated in new-user cohorts.

    Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Study long-term glargine and breast cancer.

    How was the study done?

    UK database cohort.

    How many people, animals or samples were studied?

    22,395 women.

    What was actually found?

    HR 1.44 overall; 2.23 after >5 years.

    How large was the observed effect?

    About 1.5-4 extra cases per 1000 person-years if causal (illustrative).

    What do the results mean in everyday life?

    A possible long-term signal that needs confirmation.

    What are the study's limitations?

    Observational; not replicated.

    What does it say about Elawady's specific claim?

    Partly supports the breast-cancer part.

    Do the results apply to Germany and Europe?

    UK data.

    What can explicitly not be concluded from this study?

    Cannot prove glargine causes breast cancer.

    Scientific details →

Studies contradicting or limiting the claim (4)

  • Long-term insulin glargine in early diabetes (ORIGIN)

    ORIGIN Trial Investigators; Gerstein HC et al.. N Engl J Med 2012 · PMID 22686416 · DOI 10.1056/NEJMoa1203858
    Randomised controlled trialcited by the Tayebat archivefull text, structured risk-of-bias assessment★ key study

    Over six years insulin did not change heart attacks, strokes or cancers, but caused more low-sugar episodes and 2 kg weight difference.

    Does the study support the specific claim? No · Methodological quality: high · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Does basal insulin glargine targeting normal fasting glucose reduce CV events in dysglycaemia?

    How was the study done?

    International multicentre RCT, 2x2 factorial (ORIGIN)

    How many people, animals or samples were studied?

    12,537; CV risk factors plus IFG, IGT or type 2 diabetes; mean age 63.5

    What was actually found?

    Neutral CV and cancer outcomes; more hypoglycaemia, slight weight gain.

    How large was the observed effect?

    HR 1.02 CV; HR 1.00 cancer

    What do the results mean in everyday life?

    Insulin itself did not cause heart disease or cancer in this large trial.

    What are the study's limitations?

    Open-label; funded by the glargine manufacturer; early-diabetes population on moderate doses (~28 units/day for 70 kg).

    What does it say about Elawady's specific claim?

    Key randomised evidence against C-INS-03, C-INS-05, C-INS-06; supports hypoglycaemia/weight side effects.

    Do the results apply to Germany and Europe?

    Multinational/US/UK/European data; directly transferable to Germany/EU clinical practice.

    What can explicitly not be concluded from this study?

    Safety in very high-dose, late-stage type 2 diabetes.

    Scientific details →

  • Glargine and cancer in a randomised trial

    Bordeleau L et al.. Diabetes Care 2014 · PMID 24574355 · DOI 10.2337/dc13-1468
    Randomised controlled trialindependent cross-checkabstract checked★ key study

    Cancer rates were identical with glargine and standard care (1.32 per 100 person-years each).

    Does the study support the specific claim? No · Methodological quality: high · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Effect of glargine and n-3 fatty acids on incident cancers

    How was the study done?

    Cancer substudy of the ORIGIN 2x2 factorial RCT

    How many people, animals or samples were studied?

    12,537 (953 cancer events); Dysglycaemia with high CV risk, mean age 63.5

    What was actually found?

    No difference in any cancer outcome.

    How large was the observed effect?

    1.32 vs 1.32 per 100 PY

    What do the results mean in everyday life?

    Glargine does not increase cancer within 6 years.

    What are the study's limitations?

    Industry funding; 6 years may be short for some cancers

    What does it say about Elawady's specific claim?

    Contradicts C-INS-06 and C-INS-05 (cancer).

    Do the results apply to Germany and Europe?

    Multinational trial including European sites or directly applicable to EU practice.

    What can explicitly not be concluded from this study?

    Effects after many decades.

    Scientific details →

  • Pooled studies of glargine and cancer

    Tang X et al.. PLoS One 2012 · PMID 23284776 · DOI 10.1371/journal.pone.0051814
    Meta-analysisindependent cross-checkfull text, structured risk-of-bias assessment

    Glargine was not linked to more cancer, including breast cancer.

    Does the study support the specific claim? No · Methodological quality: low · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Insulin glargine and cancer incidence

    How was the study done?

    Meta-analysis of observational studies and RCTs with GRADE

    How many people, animals or samples were studied?

    11 studies; 448,928 subjects; Diabetes patients

    What was actually found?

    OR 0.81 any cancer.

    How large was the observed effect?

    OR 0.81 (0.68-0.98)

    What do the results mean in everyday life?

    No cancer increase.

    What are the study's limitations?

    Mostly short-term observational data; very high heterogeneity; no study quality assessment; dose and long-term use not analysed; very low certainty.

    What does it say about Elawady's specific claim?

    Contradicts C-INS-06.

    Do the results apply to Germany and Europe?

    Includes European cohorts.

    What can explicitly not be concluded from this study?

    That glargine protects against cancer, or anything about dose-dependent or long-term (>5 years) breast cancer risk.

    Scientific details →

  • Glargine and breast cancer in older US women

    Bradley MC et al.. Diabetes Care 2020 · PMID 32075848 · DOI 10.2337/dc19-0614
    Cohort studyindependent cross-checkabstract checked★ key study

    Among more than 300,000 women starting insulin, glargine users did not have more breast cancer, even with longer use or higher doses.

    No breast cancer increase by duration or dose in 203,159 glargine initiators.

    Does the study support the specific claim? No · Methodological quality: high · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Compare breast cancer by insulin type.

    How was the study done?

    Medicare new-user cohort.

    How many people, animals or samples were studied?

    317,559 women >=65.

    What was actually found?

    HR 0.97 vs NPH; no dose or duration effect.

    How large was the observed effect?

    HR 0.97 (0.88-1.06).

    What do the results mean in everyday life?

    Glargine does not appear to raise breast cancer risk.

    What are the study's limitations?

    Older women only.

    What does it say about Elawady's specific claim?

    Contradicts dose-dependent cancer claim.

    Do the results apply to Germany and Europe?

    Applicable.

    What can explicitly not be concluded from this study?

    Cannot exclude small effects in younger women.

    Scientific details →

Studies with mixed or unclear results (6)

  • Review: obesity and cancer

    Calle EE et al.. Nat Rev Cancer 2004 · PMID 15286738 · DOI 10.1038/nrc1408
    Narrative reviewcited by the Tayebat archiveabstract checked

    Not assessed (no abstract available).

    Does the study support the specific claim? Unclear · Methodological quality: low · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Epidemiology and mechanisms linking overweight/obesity and cancer

    How was the study done?

    Narrative review (no abstract in PubMed; not read)

    How many people, animals or samples were studied?

    not applicable; not applicable

    What was actually found?

    Not assessed.

    How large was the observed effect?

    not applicable

    What do the results mean in everyday life?

    Not assessable.

    What are the study's limitations?

    Narrative review; Not read

    What does it say about Elawady's specific claim?

    Indirect background for C-INS-06.

    Do the results apply to Germany and Europe?

    not applicable

    What can explicitly not be concluded from this study?

    Anything about insulin injections.

    Scientific details →

  • German insurance study on glargine and cancer

    Hemkens LG et al.. Diabetologia 2009 · PMID 19565214 · DOI 10.1007/s00125-009-1418-4
    Cohort studycited by the Tayebat archivefull text, structured risk-of-bias assessment★ key study

    Without adjustment glargine users actually had slightly fewer cancers; only after statistical dose adjustment did glargine look somewhat worse, and follow-up was under 2 years.

    Does the study support the specific claim? Partly · Methodological quality: low · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Cancer and mortality risk with human insulin vs insulin analogues

    How was the study done?

    Retrospective cohort from statutory health insurance claims (AOK)

    How many people, animals or samples were studied?

    127,031; Patients starting insulin monotherapy without known cancer

    What was actually found?

    Dose-adjusted cancer HR up to 1.31 for glargine; no increase for other analogues.

    How large was the observed effect?

    Crude incidence 2.14 (glargine) vs 2.50 (human insulin) per 100 patient-years; dose-adjusted HR 1.09-1.31.

    What do the results mean in everyday life?

    An early warning signal that later trials did not confirm.

    What are the study's limitations?

    Follow-up about 1.6 years; result reverses with dose adjustment; dose computed over time at risk; no data on BMI, smoking, diabetes duration; groups clinically different.

    What does it say about Elawady's specific claim?

    Main support for C-INS-06.

    Do the results apply to Germany and Europe?

    German data; directly relevant.

    What can explicitly not be concluded from this study?

    That glargine causes cancer.

    Scientific details →

  • Swedish study of glargine and cancer

    Jonasson JM et al.. Diabetologia 2009 · PMID 19588120 · DOI 10.1007/s00125-009-1444-2
    Cohort studycited by the Tayebat archivefull text, structured risk-of-bias assessment

    Overall cancer rates were the same; women using only glargine had more breast cancer (25 cases), which the authors say may be chance.

    Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Short-term cancer incidence in glargine users (requested by EASD)

    How was the study done?

    Nationwide register-based cohort

    How many people, animals or samples were studied?

    114,841; Insulin users in Sweden

    What was actually found?

    Any cancer RR 1.07 (n.s.); breast RR 1.99 in glargine-only users.

    How large was the observed effect?

    All cancers RR 1.07 (0.91-1.27); breast cancer RR 1.99 in glargine-only women (5.0 vs 2.6 per 1,000 person-years).

    What do the results mean in everyday life?

    No clear overall cancer risk.

    What are the study's limitations?

    Only 2 years follow-up; breast signal based on 25 cases in one of many comparisons; no dose-response; many missing BMI/smoking data.

    What does it say about Elawady's specific claim?

    Limits C-INS-06 (overall null).

    Do the results apply to Germany and Europe?

    Swedish data; directly relevant.

    What can explicitly not be concluded from this study?

    Causation.

    Scientific details →

  • Glargine and breast cancer in UK women

    Suissa S et al.. Diabetologia 2011 · PMID 21614572 · DOI 10.1007/s00125-011-2190-9
    Cohort studycited by the Tayebat archivefull text, structured risk-of-bias assessment

    No increase in breast cancer during the first five years; a possible increase later in a subgroup.

    Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Long-term glargine use and breast cancer

    How was the study done?

    Matched cohort in UK GPRD

    How many people, animals or samples were studied?

    15,227 (4,579 glargine); Women >=40 with type 2 diabetes on insulin

    What was actually found?

    Overall HR 1.0; no increase in first 5 years; HR 2.7 after >5 years only in women already on insulin before glargine (10 cases).

    How large was the observed effect?

    Overall HR 1.0 (0.7-1.4); first 5 years HR 0.9 (0.7-1.3).

    What do the results mean in everyday life?

    Possible long-term question, not established.

    What are the study's limitations?

    Long-term signal based on 10 cases in one subgroup; chance possible; no dose data; some baseline differences (e.g. HRT use).

    What does it say about Elawady's specific claim?

    Mixed for C-INS-06.

    Do the results apply to Germany and Europe?

    UK data.

    What can explicitly not be concluded from this study?

    Causation.

    Scientific details →

  • How good is the evidence on long-acting insulin and cancer?

    Wu JW et al.. Diabetes Care 2016 · PMID 26740633 · DOI 10.2337/dc15-1816
    Systematic reviewindependent cross-checkabstract checked★ key study

    Most studies found no cancer increase; a few suggested more breast cancer, but many studies had design flaws.

    Most studies null for any cancer; breast cancer uncertain; methodological flaws common.

    Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Review observational studies on insulin analogues and cancer.

    How was the study done?

    Systematic review.

    How many people, animals or samples were studied?

    19 studies.

    What was actually found?

    13/15 null for any cancer; 4/13 positive for breast cancer.

    How large was the observed effect?

    Not pooled.

    What do the results mean in everyday life?

    No clear cancer risk; breast cancer still uncertain.

    What are the study's limitations?

    Short follow-up in included studies.

    What does it say about Elawady's specific claim?

    Does not support dose-dependent cancer; leaves breast question open.

    Do the results apply to Germany and Europe?

    Applicable.

    What can explicitly not be concluded from this study?

    Cannot settle long-term breast cancer risk.

    Scientific details →

  • Glargine, prior insulin use and breast cancer

    Peeters PJ et al.. Acta Oncol 2016 · PMID 27150973 · DOI 10.3109/0284186X.2016.1155736
    Cohort studyindependent cross-checkabstract checked★ key study

    Women starting with glargine had no extra breast cancer even after 5 years; a raised risk appeared only in women with long prior use of other insulins.

    No glargine-duration effect in insulin-naive women; signal only in switchers with long prior insulin.

    Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

    Original publication · Scientific details

    Study explained simply
    What did the researchers want to find out?

    Relate glargine duration to breast cancer.

    How was the study done?

    UK cohort.

    How many people, animals or samples were studied?

    12,468 women.

    What was actually found?

    No effect in new users; HR 3.17 in long-term switchers.

    How large was the observed effect?

    HR 1.06 (new users >=5 y).

    What do the results mean in everyday life?

    Glargine itself is unlikely to be the cause.

    What are the study's limitations?

    Few cases.

    What does it say about Elawady's specific claim?

    Weakens the breast-cancer claim for glargine.

    Do the results apply to Germany and Europe?

    UK data.

    What can explicitly not be concluded from this study?

    Cannot explain the switcher signal.

    Scientific details →

Regional context

Germany / EU

The signal came from German data (AOK) and was reviewed by European regulators in 2009 (EMA statement not fetched in this audit; verified: false). Glargine remains approved in the EU.

Egypt

Egypt has one of the highest diabetes prevalences in the region; the same drug classes and insulins are used. Access barriers and cost may make advice to stop medication attractive, which increases the practical risk of this claim. No Egypt-specific evidence changes the assessment.

What applies in my country?

General scientific assessment

Mostly false Glargine does not raise overall cancer risk in a dose-dependent way; a possible long-term breast-cancer signal in some UK analyses has not been confirmed by larger new-user studies.

This statement concerns biological or medical relationships. The scientific assessment above applies regardless of the country; country-specific food data do not change it.

References

  1. Long-Term Use of Long-Acting Insulin Analogs and Breast Cancer Incidence in Women With Type 2 Diabetes.. Wu JW et al.. J Clin Oncol 2017 · PMID 28953430 · DOI 10.1200/JCO.2017.73.4491
  2. Basal insulin and cardiovascular and other outcomes in dysglycemia.. ORIGIN Trial Investigators; Gerstein HC et al.. N Engl J Med 2012 · PMID 22686416 · DOI 10.1056/NEJMoa1203858
  3. The association of basal insulin glargine and/or n-3 fatty acids with incident cancers in patients with dysglycemia.. Bordeleau L et al.. Diabetes Care 2014 · PMID 24574355 · DOI 10.2337/dc13-1468
  4. Insulin glargine and cancer risk in patients with diabetes: a meta-analysis.. Tang X et al.. PLoS One 2012 · PMID 23284776 · DOI 10.1371/journal.pone.0051814
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